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A078655
a(n) = prime(k) where k = n-th prime congruent to 1 mod 6.
2
17, 41, 67, 127, 157, 191, 283, 331, 367, 401, 509, 563, 599, 709, 797, 877, 919, 967, 1087, 1171, 1217, 1297, 1409, 1447, 1523, 1741, 1787, 1847, 2027, 2081, 2221, 2269, 2351, 2477, 2549, 2609, 2719, 2803, 2909, 3019, 3067, 3229, 3299, 3469, 3559
OFFSET
1,1
LINKS
FORMULA
a(n) = A000040(A002476(n)). [Bruno Berselli, Aug 14 2012]
MATHEMATICA
With[{pc14=Select[Prime[Range[1000]], Mod[#, 6]==1&]}, Flatten[Table[Prime[Take[pc14, {n}]], {n, 100}]]] (* Vincenzo Librandi, Aug 14 2012 *)
Prime[Select[Prime[Range[100]], Mod[#, 6]==1&]] (* Harvey P. Dale, Feb 01 2022 *)
PROG
(PARI) pip(n, m, r) = {sr=0; forprime(x=3, n, if(x%m == r, v=prime(x); sr+=1.0/v; print1(v" "); ) ); print(); print("m="m" r="r" sr="sr); }
(Magma) [NthPrime(n): n in PrimesUpTo(500) | n mod 6 eq 1]; // Bruno Berselli, Aug 14 2012
CROSSREFS
Sequence in context: A269840 A237659 A350052 * A052279 A147215 A126790
KEYWORD
nonn,easy
AUTHOR
Cino Hilliard, Dec 14 2002
EXTENSIONS
Offset changed from 0 to 1 by Vincenzo Librandi, Aug 14 2012
STATUS
approved